marinated the meat in orange juice or grapefruit juice,

Instead of buying processed tenderizer, fruit juice can be used to tenderize the meat. Marinating the meat in pineapple juice or papaya juice will break down the meat fibers, and the flavor normally cooks off during grilling. It is from these fruits that many processed tenderizers are made. It is important to find a pure juice and not a pineapple or papaya drink or punch.